N₂O Emissions From Saline Of Shanxi In The Southwest China

Nitrous oxide (N2O) is one of important atmospheric greenhouse gases. Fertilization of farmland is an important atmospheric pollutant-nitrous oxide (N2O) an important man-made source of anthropogenic emissions.10% of Global saline farmland distributes in China and the research to its N2O emission characteristics is relative lack so far. Long-term observation and experimental to the N2O emission characteristics of saline, have great significance to clarify saline-alkali soil in the region and even in the national agricultural N2O emissions relative importance. Corn and wheat are the main agricultural products in China, respectively,they are 22% and 26% of the country's total acreage of arable land. Winter wheat and summer maize rotation are the main cultivating type in north China. In this thesis, the typical saline in southern China is the object of study, using the static chamber method, automatic sample boxes to observe and study its N2O emission flux dynamics, seasonal variation, annual variability and characteristics of emission factors for one year of continuous growth of maize-wheat rotation.Having a long-term observation to local conventional and non-nitrogen fertilizer (control) dealing with the maize and wheat rotation of the saline the results shows that:South of Shanxi saline wheat-maize rotation field application of nitrogen of N2O-N emission direct factor is about 1.18%, background emission rate is 2.49 kg·ha-2·a-1; N2O emissions showed seasonal variation, which is high spring and summer, and low on autumn and winter; in non-fertilization stage, soil temperature and soil moisture may be a common interpretation of changes in emissions of 45% (P<0.05); day maximum and daily variations in frequency of sunny days throughout the year were 11%; day maximum and daily variations mode occur, N2O emission flux and the temperature of the day change at the same time; intermittent artificial observations of the best measurement time was at 9:00 to 10:00 Am and revealed correction factor of non-continuous measurement. these results for understanding the laws of saline farmland N2O emissions provide a field experiment and for the preparation of agricultural N2O emission inventories as an important parameter-one year direct emission factor and emission rates in the year background provide the measured data.The paper observed only one site of the Southern Shanxi Saline wheat-maize rotation field in the N2O emission characteristics and emission factors, in order to further understand the regional and national saline N2O emissions, we need to carry out a similar long-term observation and study in different climatic zones, soil types and farm management system, but also need to adjust in-depth process mechanism to clarify the characters of the N2O emissions from vegetable spatial and temporal variation, for the preparation of emission inventories and saline-alkali soil of N2O gas emission pathways and measures, it provides the basis of observation and experiment.